class_docstr: The Ray Serve integration engine needs to have a working connection to Ray Serve. For this:
      - A Ray Serve server should be running
  
  Example:
      
code: def describe(self, key: Optional[str] = None) -> pd.DataFrame:
      args = self.model_storage.json_get("args")
      description = {
          "TRAIN_URL": [args["train_url"]],
          "PREDICT_URL": [args["predict_url"]],
          "TARGET": [args["target"]],
      }
      return pd.DataFrame.from_dict(description)
  
file_path: mindsdb/mindsdb/integrations/handlers/ray_serve_handler/ray_serve_handler.py
imports: import requests
  from typing import Dict, Optional
  import pandas
  from mindsdb.integrations.libs.base import BaseMLEngine
label_desc: Use image node_id 4 for calling the RayServeHandler obj's underlying member method code with example usage: obj.describe(key) and returns: pd